Multiple plow

ABSTRACT

A multishare plow in which the generally vertical earth-cutting edge of the plow share and mold board is tilted away from the vertical to form an obtuse angle with the horizontal cutting edge of the plow share and in which the counterslade, if any, is of small area with the result that the staggered formation of plow shares has a relatively small degree of longitudinal staggering.

United States Patent [191 Despretz [451 Mar. 26, 1974 MULTIPLE PLOW [76] Inventor: Henri Despretz, 3, Rue Des LiLas,

Chateaubriant, France 22 Filed: Aug. 8, 1972 21 Appl. No.: 278,728

Related US. Application Data [63] Continuation of Ser. No. 24,189, March 31, 1970,

abandoned.

[52] US. Cl. 172/754, 172/760 [51] Int. Cl A011) 15/00 [58] Field of Search 172/754, 760, 762, 765, 172/769, 770, 771

[56] References Cited UNITED STATES PATENTS 3,543,861 12/1970 Takakita 172/754 X 2,757,594 7/1956 Tanke 1,550,990 8/1925 Strickler et al. 172/771 3,503,453 3/1970 Johannsen et al. 172/417 X 3,036,643 5/1962 Duncanson 172/772 X 2,908,339 10/1959 Cook 172/771 X FOREIGN PATENTS OR APPLICATIONS 899,035 7/1944 France 172/754 1,188,282 4/1970 Great Britain 172/754 Primary Examiner-Robert E. Pulfrey Assistant Examiner-R. T. Rader Attorney, Agent, or Firm-Darby & Darby 5 7] ABSTRACT A= multishare plow in which the generally vertical earth-cutting edge of the plow share and mold board is tilted away from the vertical to form an obtuse angle with the horizontal cutting edge of the plow share and in which the counterslade, if any, is of small area with the result that the staggered formation of plow shares has a relatively small degree of longitudinal staggering.

6 Claims, 17 Drawing Figures PATENTEDMARZB I914 3 799273 SHEEI 1 0F 4 INVENTOR HEN DESPRETZ BY di /F;

ATTORNEYS PATENTED M826 I974 SHEEI 2 0F 4 INVENTOR HENRI DESPRETZ BY j ATTORN s PATENTEDMARZB I974 3 799.273

sum 3 OF 4 V V Z7 INVENTOR HENRI DESPRETZ ATTORN S MULTIPLE PLOW This is a continuation of application Ser. No. 24,189, filed Mar. 31, 1970, now abandoned.

The present invention relates to improvements in multishare plows.

When a plow includes a number of plowing elements, it is necessary to display them in staggered formation, not only laterally but also longitudinally. Such a longitudinal staggering or clearance is important and consequently the length of a plow including four or five shares rises to an extent which considerably reduces its possibilities of use. For example, a reversible plow including four elements adapted to plow down to 40 cm. deep is over meters long and weighs more than 2 metric tons.

The clearance referred to is essential in order to prevent the strip of earth which is cutout by the share and raised by the mold board, from being compressed against the vertical member formed by the slade of the immediately preceding plow element. In the case of a moist soil such a compression would lead to a packing effect which would interrupt the plowing operation thereby leading to a settling of the plowed up strips of earth which is not desirable when plowing.

The clearance between the shares is also essential in order to provide to the rear of the mold board a large enough space for the strip of earth which has been turned over by the next mold board to be shifted to the rear of the first-mentioned mold board without any vegetation impinging against it. This is of particular importance in the case of plowing after the harvest of corn or sorghum. In such case, a plentiful, high vegetation remains standing in the ground and should of necessity be buried.

It has also been proposed to produce a multiple plow by distributing all the plowing elements practically on a straight line and then eliminating the counter-slade and all other vertical walls in the plowing elements. Such an arrangement, however, is not satisfactory. The elimination of the vertical walls, intended in ordinary plows for the absorption of lateral stresses and the cutting out of the packing of the strips of earth against the preceding plowing elements, leads to an impact between the different strips of earth which have been plowed up and consequently the plowing obtained is extremely irregular and of a poor quality. Furthermore, there is not enough space left behind each mold board for it to afford a passage for the vegetation to be buried.

The present invention provides a multiple plow wherein the plowing elements are designed in such a manner that without cutting out the longitudinal clearance it is possible to reduce it by more than half, thus permitting the production of multiple plows the size of which are considerably less than the conventional size thereby making them suitable for use by most agriculturists.

Multishare plows executed in accordance with the invention are shorter and lighter than conventional plows so that the tractors by which they are propelled have a lesser tendency to tilt when the plow is raised at the end of the furrow, and allow the stress-control system provided on all modern tractors to act with greater accuracy.

According to the invention, the multishare plow includes a plurality of plowing elements the lateral cutting edge of which form an obtuse angle with the cutting edge of the share. Thus, there is no interference between the different strips of earth cut out and turned over, and the area along which the strips of earth pass behind the mold boards does not vary widely with the depth of plowing. This permits the length of the plow to be reduced, its weight to be lower and its cost to be reduced.

In the accompanying drawings which illustrate this invention:

FIG. 1 is a view from above of a conventional plowing element.

FIG. 2 is a view from the rear of the plowing element of FIG. 1 showing diagrammatically the different stages of the turning over of the strip of earth.

FIG. 3 is a diagrammatic vertical sectional view showing the movement of three adjacent strips of earth turned over by a multishare plow, the plowing elements of which are of a conventional type.

FIG. 4 is a view from above of a plowing element of a multishare plow according to the invention.

FIG. 5 is a view from the rear of a plowing element according to this invention, said view showing diagrammatically the successive stages of the turning over of a strip of earth.

FIG. 6 is a diagrammatic vertical sectional view showing the movement of three adjacent strips of earth turned over by a multishare plow according to the invention.

FIG. 7 is a view from above of a conventional multishare plow illustrating the passage afforded to the rear of a mold board.

FIG. 8 is a view from above of a multishare plow according to this invention showing similarly the passage afforded to the rear of the mold board.

FIG. 9 is a diagrammatic vertical sectional view illustrating by way of comparison the lateral shifting obtained with a conventional multishare plow and with a multishare plow according to the invention.

FIGS. 10 to 13 illustrate four modifications ofa plowing element according to the invention.

FIG. 14 is a view from above of the two rear elements of the plow executed according to a modification.

FIG. 15 is a lateral view corresponding to FIG. 14.

FIG. 16 is a view from the rear of the strip of earth cut out by the plow according to FIG. 14, and

FIG. 17 is a view from above of a further plow according to the invention.

Turning to FIG. 1, there is illustrated a conventional plowing element including a share 1 cutting earth horizontally and a mold board 2 adapted to make the cutout strip of earth pivot and turn around. The share 1 and mold board 2 are carried by a shaped member 3 generally termed the slade, which is secured to the beam 4. The slade 3 includes a lateral extension 3a on which is fitted a wear-resisting part or counter-slade 5. The lateral wall of the unplowed earth illustrated at 6 is cut by the lateral edges la and 2a of the share and of the mold board.

FIG. 2 illustrates diagrammatically invertical sectional view the different turning over stages of an earth strip. The earth strip of rectangular cross section is carried along by the mold board and pivots around the line A followed by the rear tip lb of the share 1 until it reaches the position b after which the mold board continues to push the strip of earth which pivots around one of its edges B, its center of gravity rising slightly until the final position c is reached, which is more or less oblique depending on the adjustment of the plow and the shape of the mold board.

In the case of a multishare plow, that is in the case of a plurality of plowing elements of the type illustrated in FIGS. 1 and 2, it is essential for such plowing elements to be distributed longitudinally in a staggered formation, the longitudinal clearance obtained being illustrated at l in FIG. 7.

As a matter of fact, if a plurality of plowing elements such as that illustrated in FIGS. 1 and 2 were arranged in parallel and in a straight line, the strip of earth cut out by a share 1 and along the edges 1a and 2a would at the very beginning of its pivoting movement engage the counter-slade of the adjacent plowing element. It is well known that as soon as a strip of somewhat heavy earth is compressed, this leads to a packing effect. In other words, an accumulation of earth between the two adjacent elements prevents the plow from becoming operative, and in the case of a gravelly soil, although the plowing may continue in spite of this packing, the plowing will be of very poor quality and of course the harvest among other factors depends on the quality of the plowing.

It has already been proposed to cut out this drawback by laying side by side on the same straight line plowing elements no longer carrying a counter-slade or any lateral wall for the slade. This would prevent the strip of earth from being compressed against such a counterslade or a similar vertical wall incorporated with the plowing element when it moves from the position a towards the position b.

However, such a solution is wholly inefficient since the compression of the plowed strips of earth against parts of the plow is replaced by a compression of said strips of earth against one another. This is illustrated in FIG. 3, which is a diagrammatic vertical sectional view showing the transverse movement of three adjacent strips of earth cut out and turned over simultaneously by a plow including three parallel shares.

FIG. 3 shows in dot-and-dash lines the initial position of the three strips of earth, in solid lines their relative position at the beginning of their movement, and lastly in interrupted lines a subsequent position. The three strips of earth pivot simultaneously and it is apparent that, since they are not longitudinally shifted with reference to one another, the right lateral surface of the first strip collides with the left lateral side of the second strip. Similarly, the right lateral side of the second strip collides with the left lateral side of the third strip. The overlapping areas are illustrated in hatched lines; in particular, the medial strip is compressed on both sides. Obviously, plowing carried out under such conditions must be of very poor quality.

The improved plow according to the present invention is constituted of plowing elements having special shape as illustrated in FIGS. 4 and 5. Such an improved plowing element includes a share and a mold board 11, both carried by a slade 12 that is a single board extending to the front and carrying no counter-slade. The shapes of the share 10 and of the mold board 11 are such that their lateral cutting edges 10a and 11a lie in a plane forming an obtuse angle of about approximately 120 with the front cutting edge 100 of the share, e.g., they are given an arcuate shape resulting in that the wall 13 along which the earth is cut forms an obtuse angle with the bottom of the furrow 14.

As illustrated in FIG. 5, the strip of earth cut out by such a plowing element has a parallelogram-shaped cross section wherein the strip d carried along by the mold board pivots around a line C followed by the end 10b of the share 10 up to the position a from which point the strip of earth rocks under the action of its own weight thereby entering its final position f.

FIG. 6 illustrates the simultaneous movement of three adjacent strips of earth cut and turned over by a three-share plow according to the invention; additionally FIG. 6 illustrates in a manner similar to FIG. 3, the different positions of the strips of earth, that is, the initial positions are drawn in dot-and-dash lines, the positions at the beginning of the movement in solid lines, and a subsequent position in interrupted lines. The three strips of earth pivot simultaneously but, by reason of this special shape assumed by them, there is no interference between their paths; the lateral sides thereof cannot collide and the earth is not compressed as before. This will be better understood if it is seen that the short diagonals X'X connecting the lateral walls of the strip form to equilateral triangles. Thus, as the strips pivot upward and reach their maximum elevation, the respective opposing lateral sides of the strips do not overlap and collide with each other, e.g., the diagonals do not overlap. It is thus possible with such improved plowing elements to reduce the longitudinal clearance between them.

It is even possible to display the different plowing elements along the same transverse line with reference to the direction of their progression without this leading to any interference between the paths followed by the turned over strips of earth. It has been found, however, that it is preferable to provide a substantial longitudinal clearance so that the plow may satisfactorily bury the vegetation met by it.

As a matter of fact, it often occurs that the plowing is to be executed in ground covered by vegetation either after a crop of sorghum has been harvested or else when it is necessary to bury lucerne or green fodder. The vegetation is then comparatively high and during its turning over it must find room for passage behind the mold board of the preceding element without impinging against it.

In FIG. 7 there is illustrated a conventional doubleshare plow provided with a clearance 1 between the two elements, which clearance is frequently of a magnitude of 800 mm. In FIG. 7, two hatched areas have been illustrated which correspond to the areas left free for burying vegetation for two different plowing depths. The strip of earth cut out by the share 1' and turned over by the mold board 2' begins pivoting around its axis, starting from the point D the position of which with reference to the mold board 2 of the adjacent plow is defined by the length of the clearance I. The dot-anddash line 25 illustrates the path of the point located at ground surface in vertical alignment with the point D when plowing at shallow depth, while the dot-and-dash line 26 illustrates the path of said point D in the case of a deep plowing. It is thus apparent that the area left free as a passage behind the mold board 2 decreases considerably with an increased depth of plowing while it is not possible in practice to reduce the length of the clearance 1 since the area for the passage of the strips of earth and of the vegetation would no longer be sufficient.

FIG. 8 illustrates the corresponding areas provided for the passage behind the mold boards as obtained with a plow according to the present invention. It is apparent that the areas available are much larger and furthermore they vary little with the depth of plowing. Such an advantage leads to a possible reduction in the length of the longitudinal clearance I while the area of the passage required for burying the vegetation is perfectly satisfactory.

FIG. 9 shows diagrammatically in vertical crosssectional view a comparison between the lateral shifting obtained with a conventional multishare plow and that obtained with a multishare plow according to the instant invention. In FIG. 9, the successive positions of a strip of earth cut and turned over by means of a conventional plow are drawn over the successive positions of a strip of earth cut and turned over by an improved plow according to the invention. The position of the center of gravity is designated by the letter G1 in the case of the conventional plow, and by the letter G2 in the case of the improved plow. As illustrated, the center of gravity G1 executes an arc of a circle as it rises and then a further arc of a circle the length of which is slightly less as it sinks, and then a third arc of a circle during which it rises slightly. The plow functions and a lateral reaction arises only during the rising section of said path. On the other hand, the center of gravity G2 follows an arc of a circle as it rises and then a further arc of a circle as it sinks, and measurements made by applicant have shown that the movement of G2 leads to a reaction on the implement the vertical component of which is slightly larger than that of the reaction produced by the movement of G1. In contradistinction, the lateral component is larger for G1 than for G2.

The greater increase in the vertical component provides no drawback and in fact provides an advantage for the plow constructed according to the invention, since it improves the penetration and vertical stability of the plow. In contradistinction, a reduction of the lateral reaction is a highly important advantage since it might have been feared that the plow would have a tendency to be shifted laterally by reason of the elimination of all lateral bearing surfaces.

FIGS. 10 to 13 illustrate four modifications providing cut earth surfaces of different shapes. It is in fact necessary to provide, in registry with the bottom of the plowed furrow, channels for the circulation of air. In the case of conventional plows, such channels are formed having a cross section which is substantially that of a right-angled triangle 6a. In contradistinction, in the case illustrated in FIG. 5, it is apparent that the plowing obtained provides no aeration channel.

In order to eliminate this drawback, it is possible to design the lateral edges of the share and the mold board in such a manner that they form a continuous curve the chord of which forms an obtuse angle with the bottom of the furrow as illustrated in FIG. 10. This provides a curvilinear earth wall 15 together with a series of aeration tunnels 15a defined by the bottom of the furrow and the curvilinear surface of the wall thus cut in the earth.

The edges of the mold board and of the share may also be designed as illustrated in FIG. 11 to lie along a dihedral constituted by a plane 16 perpendicular to the bottom of the furrow and a plane 17 oblique with reference to said bottom, the plane 16 corresponding to the lateral edge of the share. There is thus obtained an earth wall having a vertical lower section and an oblique upper section, while a plurality of small aeration channels 16a are defined by the sides of two adjacent turned over strips of earth.

It is also possible to design an edge for the mold board and the share in the manner illustrated in FIG. 12 whereby a dihedral is obtained which is reversed with reference to that illustrated in FIG. 11, since it includes in its upper section a plane 18 perpendicular to the ground surface 19 and in its lower section an oblique plane 20 forming an obtuse angle with the bottom of the furrow. In such a case, the plane 18 may be produced by the upper section of the mold board edge or else by a coulter extending to the front of the plowing element. This leads to the formation of an earth wall having an upper vertical section and a lower oblique section, the small tunnels 20a obtained in this case being defined by the dihedrals out in the strips of earth.

It is also possible, as illustrated in FIG. 13, to resort to edges for the mold board and for the share such that the cut earth wall includes a lower section which is incurved at 21 while the upper section is flat as shown at 22. The tunnels 21a formed in this case are very similar to the tunnels 15a of FIG. 10.

The plows according to FIGS. 10, 12 and 13 should provide improved results compared with conventional plows as concerns the aeration of the soil. It is necessary to provide such aerating tunnels when plowing and it is also essential to remove them by suitable implements when a seed bed is being prepared. Tunnels, such as that illustrated at 6a in FIG. 2, obtained with conventional plows have their sides formed by two different strips of earth which engage each other and mutually improve their resistance. It is therefore necessary to break through the strips of earth during the subsequent preparation of the soil in order to completely destroy such tunnels. If the agriculturist plows deep furrows, he risks leaving in position cavities in the ground. In contradistinction, tunnels such as 15a, 20a, 21a which are provided with a comparatively flat wall formed in a single strip of earth have a tendency to collapse automatically after a short time thereby lessening the risk of leaving cavities in the ground.

FIGS. 14 to 16 illustrate a further embodiment of the mold board of the multishare plow according to the invention. In fact, it has appeared during experiments that the lateral stability was improved by equipping at least one of the last plowing elements with a vertical counter-slade of a reduced height engaging a small vertical wall formed by the share in the ground.

In FIG. 14, there is illustrated in dot-and-dash lines the rear section of the plow frame and the last plowing elements 40 and 41 of the multishare plow. These different elements are connected with the frame by a slade 12. The rearmost element 41 includes a number of parts similar to those of the preceding elements, chiefly the operating implements such as the share 42, the mold board 43 of which the front edge producing the sloping earth wall is in the shape of a replaceable stem post 44. It is understood that in grounds which produce no great wear on the parts of the plow, such a removable stem post is not of interest and the mold board is constituted as a unitary part.

The stem post 44 may be secured in different manners, for example by means of two straps on the mold board or else as illustrated in FIG. 15 on the board forming the slade 12. It is necessary to carefully design the connection between the stem post and the share in order to prevent any wedging in contact with roots or vegetation. The share 42 may be executed in various known manners, e.g., as a blade, a flat-nosed share, a two-part share provided with a removable wearresisting tip or the like and similarly the mold board may assume various shapes such as a helical, cylindrohelical or the like shape.

In order to absorb the lateral reaction of the plow, the elements may be equipped with a counter-slade 45 such as that illustrated in FIGS. 1 and 2 adapted to bear against a small vertical earth wall 46 produced by the flange on the share 42. Said counter-slade is secured conventionally by two bolts 47 on a vertical board fitted on the rearmost slade 12 while it is provided with a reinforcing strut 48 (FIG. 15).

Depending on the type of earth which is to be plowed, it may be necessary to increase the carrier surface of the counter-slade when the lateral reactions are too large. For this purpose, there is provided a vertical fin including a blade 49 pivotally secured to the rear of the eounterslade 45 around the transverse axis 50 and held in position by a spring 51. This vertical fin engages the ground, insuring excellent stability for the plow (FIG. 15).

The strip of earth cut by the mold board 43 or its stem post 44 is illustrated in FIG. 16; the shape of the element designed as described produces a small vertical earth wall 46 followed by a concave sloping wall section flaring away from the horizontal cutting plane defined by the share. The strip of earth 52 drawn in dot-and-dash lines, turned over by the mold board 43, is shifted by it into the position 53.

Preferably, the cutting section of the mold board producing the oblique section of the earth wall is connected with the share in a manner such that said cutting edge extends outwardly with reference to the direction of progression of the plow in order to reduce engagement with roots or vegetation lying at ground level.

FIG. 17 illustrates a multishare plow including a plowing element similar to that illustrated in FIG, and designed to considerably reduce the longitudinal clearance between the successive elements.

This plow includes a fore-carriage 30 adapted to be coupled with the connecting bars of a tractor and a frame 31 to which are secured the slades 12 carrying the shares and mold boards 11. The lateral reaction produced by the earth on the plowing elements is absorbed by the furrow wheel 32. The lateral edge 11a of the mold board 11 acts as a coulter and cuts the earth without tearing it out, the removal being produced by a conventional mold board which is not fitted with a coulter.

It is also possible in the case of conventional plows to provide a plurality of small superficially acting shares 33 adapted to improve the burying of the organic matter remaining at ground surface.

Excellent results have been obtained with a plow such as that illustrated in FIG. 17, the longitudinal clearance between the plowing elements being equal to only 300 mm. whereas, in the case of conventional plows, it would be necessary to provide a longitudinal clearance of 800 mm.

Obviously the plow elements described can be fitted on any known type of plow producing either a plowing in lands as in the case of a simple plow or else a flat plowing as in the case of an alternating, balance, quarter turn or reversible plow.

What I claim is:

l. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard shaped for pivoting cutout earth through not more than and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said oblique lateral surface and said generally plane horizontal surface subtending an obtuse angle of approximately whereby the re quired longitudinal spacing between the plowing elements of said plow is reduced.

2. A multishare plow as recited in claim 1, wherein said lateral furrow cutting edge projection consists of a plane perpendicular to the bottom of the plowed furrow and a surface oblique with reference to the bottom of the plowed furrow, the perpendicular plane being at the lower end of said surface whereby the cutout earth wall is made to define a vertical lower section and an oblique upper section and a plurality of aeration channels are defined by the sides of adjacent cutout strips of earth.

3. A multishare plow having a predetermined direction of travel comprising a plurality of spaced plowing elements including a rearmost plowing element, each of said elements including a moldboard shaped for pivoting cutout earth through not more than 90, said rearmost plowing element having means for stabilizing said plow by resting against a portion of a plowed furrow wall, said means including a fin on the lower end thereof and a support member for said fin attached to a portion of said rearmost plowing element, each of said elements further including a lateral furrow cutting edge at the forward end of said moldboard, said lateral furrow cutting edge and a line extending in the prede termined direction of travel of said plow defining a first surface, and a share connected to said moldboard and having a horizontal cutting edge, said horizontal cutting edge and the line extending in said predetermined direction of travel defining a substantially plane second surface, said first and second surfaces defining an obtuse angle of substantially more than 90 thereby preventing the collision of earth strips cutout by adjacent plowing elements while reducing the required longitudinal clearance between said plowing elements.

4. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard shaped for pivoting cutout earth through not more than 90 and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the lateral furrow cutting edge forms a convex curve which forms a concave surface in the bottom of the overturned earth to provide an aeration channel defined by the bottom of a plowed furrow and the curvilinear surface of the cutout earth wall in said furrow, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said oblique lateral surface and said generally plane horizontal surface subtending an obtuse a rgle of approximately 120 whereby the re: quired longitudinal spacing between the plowing elements of said plow is reduced.

5. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard shaped for pivoting cutout earth through not more than 90 and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said lateral furrow cutting edge projection consisting of a plane perpendicular to the bottom of the plowed furrow and a surface oblique with reference to the bottom of the plowed furrow, the perpendicular plane being at the lower end of said surface whereby the cutout earth wall is made to define a vertical lower section and an oblique upper section and a plurality of aeration channels are defined by the sides of adjacent cutout strips of earth, said oblique lateral surface and said generally plane horizontal surface subtending an obtuse angle of approximately 120 whereby the required longitudinal spacing between the plowing elements of said plow is reduced.

6. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing-elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said moldboard being shaped for pivoting cutout earth through not more than about an axis defined by the line extending in the predetermined direction of travel of said plow and passing through the end of said horizontal cutting edge remote from said lateral furrow cutting edge, and said oblique lateral surface and said generally plane horizontal surface subtending an obtuse angle of approximately whereby the required longitudinal spacing between the plowing elements of said plow is reduced. 

1. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard shaped for pivoting cutout earth through not more than 90* and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said oblique lateral surface and said generally plane horizontal surface subtending an obtuse angle of approximately 120* whereby the required longitudinal spacing between the plowing elements of said plow is reduced.
 2. A multishare plow as recited in claim 1, wherein said lateral furrow cutting edge projection consists of a plane perpendicular to the bottom of the plowed furrow and a surface oblique with reference to the bottom of the plowed furrow, the perpendicular plane being at the lower end of said surface whereby the cutout earth wall is made to define a vertical lower section and an oblique upper section and a plurality of aeration channels are defined by the sides of adjacent cutout strips of earth.
 3. A multishare plow having a predetermined direction of travel comprising a plurality of spaced plowing elements including a rearmost plowing element, each of said elements including a moldboard shaped for pivoting cutout earth through not more than 90*, said rearmost plowing element having means for stabilizing said plow by resting against a portion of a plowed furrow wall, said means including a fin on the lower end thereof and a support member for said fin attached to a portion of said rearmost plowing element, each of said elements further including a lateral furrow cutting edge at the forward end of said moldboard, said lateral furrow cutting edge and a line extending in the predetermined direction of travel of said plow defining a first surface, and a share connected to said moldboard and having a horizontal cutting edge, said horizontal cutting edge and the line extending in said predetermined direction of travel defining a substantially plane second surface, said firSt and second surfaces defining an obtuse angle of substantially more than 90* thereby preventing the collision of earth strips cutout by adjacent plowing elements while reducing the required longitudinal clearance between said plowing elements.
 4. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard shaped for pivoting cutout earth through not more than 90* and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the lateral furrow cutting edge forms a convex curve which forms a concave surface in the bottom of the overturned earth to provide an aeration channel defined by the bottom of a plowed furrow and the curvilinear surface of the cutout earth wall in said furrow, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said oblique lateral surface and said generally plane horizontal surface subtending an obtuse angle of approximately 120* whereby the required longitudinal spacing between the plowing elements of said plow is reduced.
 5. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard shaped for pivoting cutout earth through not more than 90* and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said lateral furrow cutting edge projection consisting of a plane perpendicular to the bottom of the plowed furrow and a surface oblique with reference to the bottom of the plowed furrow, the perpendicular plane being at the lower end of said surface whereby the cutout earth wall is made to define a vertical lower section and an oblique upper section and a plurality of aeration channels are defined by the sides of adjacent cutout strips of earth, said oblique lateral surface and said generally plane horizontal surface subtending an obtuse angle of approximately 120* whereby the required longitudinal spacing between the plowing elements of said plow is reduced.
 6. A multishare plow arrangement having a predetermined direction of travel comprising a plurality of plowing-elements for plowing a plurality of adjacent furrows, each of said plowing elements having a moldboard and having a lateral furrow cutting edge at the forward end thereof, the projection of said lateral furrow cutting edge extending parallel to the direction of travel of said plow defining an oblique lateral surface corresponding to the side of a furrow, and a share connected to said moldboard and having a generally horizontal cutting edge, the projection of said horizontal cutting edge extending in said direction of travel defining a generally plane horizontal surface corresponding to the bottom of a furrow, said moldboard being shaped for pivoting cutout earth through not more than 90* about an axis defined by the line extending in the predetermined direction of travel of said plow and passing through the end of said horizontal cutting edge remote from said lateral furrow cutting edge, and said oblique latEral surface and said generally plane horizontal surface subtending an obtuse angle of approximately 120* whereby the required longitudinal spacing between the plowing elements of said plow is reduced. 